The Tcpdump Group git mirrors - tcpdump/blob - print-vtp.c

   1 /*
   2  * Copyright (c) 1998-2007 The TCPDUMP project
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that: (1) source code
   6  * distributions retain the above copyright notice and this paragraph
   7  * in its entirety, and (2) distributions including binary code include
   8  * the above copyright notice and this paragraph in its entirety in
   9  * the documentation or other materials provided with the distribution.
  10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  13  * FOR A PARTICULAR PURPOSE.
  14  *
  15  * VLAN TRUNKING PROTOCOL (VTP)
  16  *
  17  * Reference documentation:
  18  *  http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080094c52.shtml
  19  *  http://www.cisco.com/warp/public/473/21.html
  20  *  http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
  21  *
  22  * Original code ode by Carles Kishimoto <carles.kishimoto@gmail.com>
  23  */
  24
  25 #define NETDISSECT_REWORKED
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include <tcpdump-stdinc.h>
  31
  32 #include "interface.h"
  33 #include "addrtoname.h"
  34 #include "extract.h"
  35
  36 #define VTP_HEADER_LEN                  36
  37 #define VTP_DOMAIN_NAME_LEN             32
  38 #define VTP_MD5_DIGEST_LEN              16
  39 #define VTP_UPDATE_TIMESTAMP_LEN        12
  40 #define VTP_VLAN_INFO_OFFSET            12
  41
  42 #define VTP_SUMMARY_ADV                 0x01
  43 #define VTP_SUBSET_ADV                  0x02
  44 #define VTP_ADV_REQUEST                 0x03
  45 #define VTP_JOIN_MESSAGE                0x04
  46
  47 struct vtp_vlan_ {
  48     u_int8_t  len;
  49     u_int8_t  status;
  50     u_int8_t  type;
  51     u_int8_t  name_len;
  52     u_int16_t vlanid;
  53     u_int16_t mtu;
  54     u_int32_t index;
  55 };
  56
  57 static const struct tok vtp_message_type_values[] = {
  58     { VTP_SUMMARY_ADV, "Summary advertisement"},
  59     { VTP_SUBSET_ADV, "Subset advertisement"},
  60     { VTP_ADV_REQUEST, "Advertisement request"},
  61     { VTP_JOIN_MESSAGE, "Join message"},
  62     { 0, NULL }
  63 };
  64
  65 static const struct tok vtp_header_values[] = {
  66     { 0x01, "Followers"}, /* On Summary advertisement, 3rd byte is Followers */
  67     { 0x02, "Seq number"}, /* On Subset  advertisement, 3rd byte is Sequence number */
  68     { 0x03, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */
  69     { 0x04, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */
  70     { 0, NULL }
  71 };
  72
  73 static const struct tok vtp_vlan_type_values[] = {
  74     { 0x01, "Ethernet"},
  75     { 0x02, "FDDI"},
  76     { 0x03, "TrCRF"},
  77     { 0x04, "FDDI-net"},
  78     { 0x05, "TrBRF"},
  79     { 0, NULL }
  80 };
  81
  82 static const struct tok vtp_vlan_status[] = {
  83     { 0x00, "Operational"},
  84     { 0x01, "Suspended"},
  85     { 0, NULL }
  86 };
  87
  88 #define VTP_VLAN_SOURCE_ROUTING_RING_NUMBER      0x01
  89 #define VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER    0x02
  90 #define VTP_VLAN_STP_TYPE                        0x03
  91 #define VTP_VLAN_PARENT_VLAN                     0x04
  92 #define VTP_VLAN_TRANS_BRIDGED_VLAN              0x05
  93 #define VTP_VLAN_PRUNING                         0x06
  94 #define VTP_VLAN_BRIDGE_TYPE                     0x07
  95 #define VTP_VLAN_ARP_HOP_COUNT                   0x08
  96 #define VTP_VLAN_STE_HOP_COUNT                   0x09
  97 #define VTP_VLAN_BACKUP_CRF_MODE                 0x0A
  98
  99 static const struct tok vtp_vlan_tlv_values[] = {
 100     { VTP_VLAN_SOURCE_ROUTING_RING_NUMBER, "Source-Routing Ring Number TLV"},
 101     { VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER, "Source-Routing Bridge Number TLV"},
 102     { VTP_VLAN_STP_TYPE, "STP type TLV"},
 103     { VTP_VLAN_PARENT_VLAN, "Parent VLAN TLV"},
 104     { VTP_VLAN_TRANS_BRIDGED_VLAN, "Translationally bridged VLANs TLV"},
 105     { VTP_VLAN_PRUNING, "Pruning TLV"},
 106     { VTP_VLAN_BRIDGE_TYPE, "Bridge Type TLV"},
 107     { VTP_VLAN_ARP_HOP_COUNT, "Max ARP Hop Count TLV"},
 108     { VTP_VLAN_STE_HOP_COUNT, "Max STE Hop Count TLV"},
 109     { VTP_VLAN_BACKUP_CRF_MODE, "Backup CRF Mode TLV"},
 110     { 0,                                  NULL }
 111 };
 112
 113 static const struct tok vtp_stp_type_values[] = {
 114     { 1, "SRT"},
 115     { 2, "SRB"},
 116     { 3, "Auto"},
 117     { 0, NULL }
 118 };
 119
 120 void
 121 vtp_print (netdissect_options *ndo,
 122            const u_char *pptr, u_int length)
 123 {
 124     int type, len, tlv_len, tlv_value;
 125     const u_char *tptr;
 126     const struct vtp_vlan_ *vtp_vlan;
 127
 128     if (length < VTP_HEADER_LEN)
 129         goto trunc;
 130
 131     tptr = pptr;
 132
 133     if (!ND_TTEST2(*tptr, VTP_HEADER_LEN))
 134         goto trunc;
 135
 136     type = *(tptr+1);
 137     ND_PRINT((ndo, "VTPv%u, Message %s (0x%02x), length %u",
 138            *tptr,
 139            tok2str(vtp_message_type_values,"Unknown message type", type),
 140            *(tptr+1),
 141            length));
 142
 143     /* In non-verbose mode, just print version and message type */
 144     if (ndo->ndo_vflag < 1) {
 145         return;
 146     }
 147
 148     /* verbose mode print all fields */
 149     ND_PRINT((ndo, "\n\tDomain name: %s, %s: %u",
 150            (tptr+4),
 151            tok2str(vtp_header_values,"Unknown",*(tptr+1)),
 152            *(tptr+2)));
 153
 154     tptr += VTP_HEADER_LEN;
 155
 156     switch (type) {
 157
 158     case VTP_SUMMARY_ADV:
 159
 160         /*
 161          *  SUMMARY ADVERTISEMENT
 162          *
 163          *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 164          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 165          *  |     Version   |     Code      |    Followers  |    MmgtD Len  |
 166          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 167          *  |                    Management Domain Name                     |
 168          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 169          *  |                    Configuration revision number              |
 170          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 171          *  |                  Updater Identity IP address                  |
 172          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 173          *  |                    Update Timestamp (12 bytes)                |
 174          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 175          *  |                        MD5 digest (16 bytes)                  |
 176          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 177          *
 178          */
 179
 180         ND_PRINT((ndo, "\n\t  Config Rev %x, Updater %s",
 181                EXTRACT_32BITS(tptr),
 182                ipaddr_string(ndo, tptr+4)));
 183         tptr += 8;
 184         ND_PRINT((ndo, ", Timestamp 0x%08x 0x%08x 0x%08x",
 185                EXTRACT_32BITS(tptr),
 186                EXTRACT_32BITS(tptr + 4),
 187                EXTRACT_32BITS(tptr + 8)));
 188         tptr += VTP_UPDATE_TIMESTAMP_LEN;
 189         ND_PRINT((ndo, ", MD5 digest: %08x%08x%08x%08x",
 190                EXTRACT_32BITS(tptr),
 191                EXTRACT_32BITS(tptr + 4),
 192                EXTRACT_32BITS(tptr + 8),
 193                EXTRACT_32BITS(tptr + 12)));
 194         tptr += VTP_MD5_DIGEST_LEN;
 195         break;
 196
 197     case VTP_SUBSET_ADV:
 198
 199         /*
 200          *  SUBSET ADVERTISEMENT
 201          *
 202          *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 203          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 204          *  |     Version   |     Code      |   Seq number  |    MmgtD Len  |
 205          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 206          *  |                    Management Domain Name                     |
 207          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 208          *  |                    Configuration revision number              |
 209          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 210          *  |                         VLAN info field 1                     |
 211          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 212          *  |                         ................                      |
 213          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 214          *  |                         VLAN info field N                     |
 215          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 216          *
 217          */
 218
 219         ND_PRINT((ndo, ", Config Rev %x", EXTRACT_32BITS(tptr)));
 220
 221         /*
 222          *  VLAN INFORMATION
 223          *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 224          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 225          *  | V info len    |    Status     |  VLAN type    | VLAN name len |
 226          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 227          *  |       ISL vlan id             |            MTU size           |
 228          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 229          *  |                     802.10 index (SAID)                       |
 230          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 231          *  |                         VLAN name                             |
 232          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 233          *
 234          */
 235
 236         tptr += 4;
 237         while (tptr < (pptr+length)) {
 238
 239             len = *tptr;
 240             if (len == 0)
 241                 break;
 242
 243             if (!ND_TTEST2(*tptr, len))
 244                 goto trunc;
 245
 246             vtp_vlan = (struct vtp_vlan_*)tptr;
 247             ND_PRINT((ndo, "\n\tVLAN info status %s, type %s, VLAN-id %u, MTU %u, SAID 0x%08x, Name %s",
 248                    tok2str(vtp_vlan_status,"Unknown",vtp_vlan->status),
 249                    tok2str(vtp_vlan_type_values,"Unknown",vtp_vlan->type),
 250                    EXTRACT_16BITS(&vtp_vlan->vlanid),
 251                    EXTRACT_16BITS(&vtp_vlan->mtu),
 252                    EXTRACT_32BITS(&vtp_vlan->index),
 253                    (tptr + VTP_VLAN_INFO_OFFSET)));
 254
 255             /*
 256              * Vlan names are aligned to 32-bit boundaries.
 257              */
 258             len  -= VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4);
 259             tptr += VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4);
 260
 261             /* TLV information follows */
 262
 263             while (len > 0) {
 264
 265                 /*
 266                  * Cisco specs says 2 bytes for type + 2 bytes for length, take only 1
 267                  * See: http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
 268                  */
 269                 type = *tptr;
 270                 tlv_len = *(tptr+1);
 271
 272                 ND_PRINT((ndo, "\n\t\t%s (0x%04x) TLV",
 273                        tok2str(vtp_vlan_tlv_values, "Unknown", type),
 274                        type));
 275
 276                 /*
 277                  * infinite loop check
 278                  */
 279                 if (type == 0 || tlv_len == 0) {
 280                     return;
 281                 }
 282
 283                 if (!ND_TTEST2(*tptr, tlv_len*2 +2))
 284                     goto trunc;
 285
 286                 tlv_value = EXTRACT_16BITS(tptr+2);
 287
 288                 switch (type) {
 289                 case VTP_VLAN_STE_HOP_COUNT:
 290                     ND_PRINT((ndo, ", %u", tlv_value));
 291                     break;
 292
 293                 case VTP_VLAN_PRUNING:
 294                     ND_PRINT((ndo, ", %s (%u)",
 295                            tlv_value == 1 ? "Enabled" : "Disabled",
 296                            tlv_value));
 297                     break;
 298
 299                 case VTP_VLAN_STP_TYPE:
 300                     ND_PRINT((ndo, ", %s (%u)",
 301                            tok2str(vtp_stp_type_values, "Unknown", tlv_value),
 302                            tlv_value));
 303                     break;
 304
 305                 case VTP_VLAN_BRIDGE_TYPE:
 306                     ND_PRINT((ndo, ", %s (%u)",
 307                            tlv_value == 1 ? "SRB" : "SRT",
 308                            tlv_value));
 309                     break;
 310
 311                 case VTP_VLAN_BACKUP_CRF_MODE:
 312                     ND_PRINT((ndo, ", %s (%u)",
 313                            tlv_value == 1 ? "Backup" : "Not backup",
 314                            tlv_value));
 315                     break;
 316
 317                     /*
 318                      * FIXME those are the defined TLVs that lack a decoder
 319                      * you are welcome to contribute code ;-)
 320                      */
 321
 322                 case VTP_VLAN_SOURCE_ROUTING_RING_NUMBER:
 323                 case VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER:
 324                 case VTP_VLAN_PARENT_VLAN:
 325                 case VTP_VLAN_TRANS_BRIDGED_VLAN:
 326                 case VTP_VLAN_ARP_HOP_COUNT:
 327                 default:
 328                     print_unknown_data(ndo, tptr, "\n\t\t  ", 2 + tlv_len*2);
 329                     break;
 330                 }
 331                 len -= 2 + tlv_len*2;
 332                 tptr += 2 + tlv_len*2;
 333             }
 334         }
 335         break;
 336
 337     case VTP_ADV_REQUEST:
 338
 339         /*
 340          *  ADVERTISEMENT REQUEST
 341          *
 342          *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 343          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 344          *  |     Version   |     Code      |   Reserved    |    MmgtD Len  |
 345          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 346          *  |                    Management Domain Name                     |
 347          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 348          *  |                          Start value                          |
 349          *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 350          *
 351          */
 352
 353         ND_PRINT((ndo, "\n\tStart value: %u", EXTRACT_32BITS(tptr)));
 354         break;
 355
 356     case VTP_JOIN_MESSAGE:
 357
 358         /* FIXME - Could not find message format */
 359         break;
 360
 361     default:
 362         break;
 363     }
 364
 365     return;
 366
 367  trunc:
 368     ND_PRINT((ndo, "[|vtp]"));
 369 }
 370
 371 /*
 372  * Local Variables:
 373  * c-style: whitesmith
 374  * c-basic-offset: 4
 375  * End:
 376  */